In the progress of connected natural phenomena from east to west, that great law of nature is plainly revealed which has so often and evidently manifested itself in the earth's organism, as well as in the state of nations dependent upon it. In the inmost depths of the globe that impulse was given in the year 1333, which in uninterrupted succession for six and twenty years shook the surface of the earth, even to the western shores of Europe. From the very beginning the air partook of the terrestrial concussion, atmospherical waters overflowed the land, or its plants and animals perished under the scorching heat. The insect tribe was wonderfully called into life, as if animated beings were destined to complete the destruction which astral and telluric powers had begun. Thus did this dreadful work of nature advance from year to year; it was a progressive infection of the zones, which exerted a powerful influence both above and beneath the surface of the earth; and after having been perceptible in slighter indications, at the commencement of the terrestrial commotions in China, convulsed the whole earth. The nature of the first plague in China is unknown. We have no certain intelligence of the disease until it entered the western countries of Asia. Here it showed itself as the Oriental plague, with inflammation of the lungs; in which form it probably also may have begun in China, that is to say, as a malady which spreads, more than any other, by contagion--a contagion that, in ordinary pestilences, requires immediate contact, and only under favourable circumstances of rare occurrence is communicated by the mere approach to the sick. The share which this cause had in the spreading of the plague over the whole earth was certainly very great; and the opinion that the Black Death might have been excluded from Western Europe by good regulations, similar to those which are now in use, would have all the support of modern experience, provided it could be proved that this plague had been actually imported from the East, or that the Oriental plague in general, whenever it appears in Europe, has its origin in Asia or Egypt. Such a proof, however, can by no means be produced so as to enforce conviction; for it would involve the impossible assumption, either that there is no essential difference between the degree of civilisation of the European nations, in the most ancient and in modern times, or that detrimental circumstances, which have yielded only to the civilisation of human society and the regular cultivation of countries, could not formerly keep up the glandular plague.